AirHint found the following cheapest return flights from Boston (BOS) to Copenhagen (CPH) in September 2025 (see full year).

Return flights

01 Sep - 08 Sep	Air Canada
06 Sep - 15 Sep	Air Canada
11 Sep - 18 Sep	Air Canada
01 Sep - 09 Sep	Air France
01 Sep - 09 Sep	Scandinavian Airlines	direct
01 Sep - 08 Sep	Scandinavian Airlines	direct
30 Sep - 07 Oct	Scandinavian Airlines	direct
24 Sep - 01 Oct	Icelandair
03 Sep - 10 Sep	Icelandair
09 Sep - 16 Sep	Icelandair
17 Sep - 24 Sep	Icelandair
16 Sep - 02 Oct	Air France
21 Sep - 28 Sep	Icelandair
27 Sep - 04 Oct	Scandinavian Airlines	direct

Also check the deals for one-way flights from Boston to Copenhagen in September.

The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.

Book a cheap hotel in Copenhagen

Cheap car rent in Copenhagen

Cheapest return flights from Boston to Copenhagen in September from 363€

Return flights